Nothing new . Metric system versus Imperial has been talked about in various governments since about the mid 1800s. Shouldn't be too difficult for children to learn the Imperial system. At the moment some of the measurements they use in every day language include---mileage ,speeds, shoe sizes, dress sizes, pint of milk etc.
Think of all the idioms that we will keep. 'They stood miles apart', 'He inched closer to me', 'Give them an inch and they will take a mile'. try using metric for these and somehow it doesn't seem right and those are just a few.
There are dual scales in use now and I suppose that the customer will be able to ask for their goods in either measurement. Tinned goods are usually marked in grams so I don't suppose that will alter.